Balance and Stability:
Proprioception is closely linked to balance and stability. It provides feedback to the brain regarding body position and center of gravity, helping maintain equilibrium. The information received through proprioceptive receptors assists in adjusting muscle tension and joint movements to prevent falls and maintain stability.
The above is an extract from the following article:
psychology.tips/propriocept...
I am no expert but it makes sense that using additional sensory input (ie weighted vest etc) can help increase the signal to let our brain know where our bodies are in space.